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1<?xml version="1.0" encoding="UTF-8" standalone="no"?>2<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><meta http-equiv="Content-Type" content="text/html; charset=UTF-8" /><title>DROP FUNCTION</title><link rel="stylesheet" type="text/css" href="stylesheet.css" /><link rev="made" href="pgsql-docs@lists.postgresql.org" /><meta name="generator" content="DocBook XSL Stylesheets Vsnapshot" /><link rel="prev" href="sql-dropforeigntable.html" title="DROP FOREIGN TABLE" /><link rel="next" href="sql-dropgroup.html" title="DROP GROUP" /></head><body id="docContent" class="container-fluid col-10"><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="5" align="center">DROP FUNCTION</th></tr><tr><td width="10%" align="left"><a accesskey="p" href="sql-dropforeigntable.html" title="DROP FOREIGN TABLE">Prev</a> </td><td width="10%" align="left"><a accesskey="u" href="sql-commands.html" title="SQL Commands">Up</a></td><th width="60%" align="center">SQL Commands</th><td width="10%" align="right"><a accesskey="h" href="index.html" title="PostgreSQL 16.3 Documentation">Home</a></td><td width="10%" align="right"> <a accesskey="n" href="sql-dropgroup.html" title="DROP GROUP">Next</a></td></tr></table><hr /></div><div class="refentry" id="SQL-DROPFUNCTION"><div class="titlepage"></div><a id="id-1.9.3.114.1" class="indexterm"></a><div class="refnamediv"><h2><span class="refentrytitle">DROP FUNCTION</span></h2><p>DROP FUNCTION — remove a function</p></div><div class="refsynopsisdiv"><h2>Synopsis</h2><pre class="synopsis">3DROP FUNCTION [ IF EXISTS ] <em class="replaceable"><code>name</code></em> [ ( [ [ <em class="replaceable"><code>argmode</code></em> ] [ <em class="replaceable"><code>argname</code></em> ] <em class="replaceable"><code>argtype</code></em> [, ...] ] ) ] [, ...]4    [ CASCADE | RESTRICT ]5</pre></div><div class="refsect1" id="id-1.9.3.114.5"><h2>Description</h2><p>6   <code class="command">DROP FUNCTION</code> removes the definition of an existing7   function. To execute this command the user must be the8   owner of the function. The argument types to the9   function must be specified, since several different functions10   can exist with the same name and different argument lists.11  </p></div><div class="refsect1" id="id-1.9.3.114.6"><h2>Parameters</h2><div class="variablelist"><dl class="variablelist"><dt><span class="term"><code class="literal">IF EXISTS</code></span></dt><dd><p>12      Do not throw an error if the function does not exist. A notice is issued13      in this case.14     </p></dd><dt><span class="term"><em class="replaceable"><code>name</code></em></span></dt><dd><p>15      The name (optionally schema-qualified) of an existing function.  If no16      argument list is specified, the name must be unique in its schema.17     </p></dd><dt><span class="term"><em class="replaceable"><code>argmode</code></em></span></dt><dd><p>18      The mode of an argument: <code class="literal">IN</code>, <code class="literal">OUT</code>,19      <code class="literal">INOUT</code>, or <code class="literal">VARIADIC</code>.20      If omitted, the default is <code class="literal">IN</code>.21      Note that <code class="command">DROP FUNCTION</code> does not actually pay22      any attention to <code class="literal">OUT</code> arguments, since only the input23      arguments are needed to determine the function's identity.24      So it is sufficient to list the <code class="literal">IN</code>, <code class="literal">INOUT</code>,25      and <code class="literal">VARIADIC</code> arguments.26     </p></dd><dt><span class="term"><em class="replaceable"><code>argname</code></em></span></dt><dd><p>27      The name of an argument.28      Note that <code class="command">DROP FUNCTION</code> does not actually pay29      any attention to argument names, since only the argument data30      types are needed to determine the function's identity.31     </p></dd><dt><span class="term"><em class="replaceable"><code>argtype</code></em></span></dt><dd><p>32      The data type(s) of the function's arguments (optionally33      schema-qualified), if any.34     </p></dd><dt><span class="term"><code class="literal">CASCADE</code></span></dt><dd><p>35      Automatically drop objects that depend on the function (such as36      operators or triggers),37      and in turn all objects that depend on those objects38      (see <a class="xref" href="ddl-depend.html" title="5.14. Dependency Tracking">Section 5.14</a>).39     </p></dd><dt><span class="term"><code class="literal">RESTRICT</code></span></dt><dd><p>40      Refuse to drop the function if any objects depend on it.  This41      is the default.42     </p></dd></dl></div></div><div class="refsect1" id="SQL-DROPFUNCTION-EXAMPLES"><h2>Examples</h2><p>43   This command removes the square root function:44 45</p><pre class="programlisting">46DROP FUNCTION sqrt(integer);47</pre><p>48   Drop multiple functions in one command:49</p><pre class="programlisting">50DROP FUNCTION sqrt(integer), sqrt(bigint);51</pre><p>52   If the function name is unique in its schema, it can be referred to without53   an argument list:54</p><pre class="programlisting">55DROP FUNCTION update_employee_salaries;56</pre><p>57   Note that this is different from58</p><pre class="programlisting">59DROP FUNCTION update_employee_salaries();60</pre><p>61   which refers to a function with zero arguments, whereas the first variant62   can refer to a function with any number of arguments, including zero, as63   long as the name is unique.64  </p></div><div class="refsect1" id="SQL-DROPFUNCTION-COMPATIBILITY"><h2>Compatibility</h2><p>65   This command conforms to the SQL standard, with66   these <span class="productname">PostgreSQL</span> extensions:67   </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>The standard only allows one function to be dropped per command.</p></li><li class="listitem"><p>The <code class="literal">IF EXISTS</code> option</p></li><li class="listitem"><p>The ability to specify argument modes and names</p></li></ul></div></div><div class="refsect1" id="id-1.9.3.114.9"><h2>See Also</h2><span class="simplelist"><a class="xref" href="sql-createfunction.html" title="CREATE FUNCTION"><span class="refentrytitle">CREATE FUNCTION</span></a>, <a class="xref" href="sql-alterfunction.html" title="ALTER FUNCTION"><span class="refentrytitle">ALTER FUNCTION</span></a>, <a class="xref" href="sql-dropprocedure.html" title="DROP PROCEDURE"><span class="refentrytitle">DROP PROCEDURE</span></a>, <a class="xref" href="sql-droproutine.html" title="DROP ROUTINE"><span class="refentrytitle">DROP ROUTINE</span></a></span></div></div><div class="navfooter"><hr /><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="sql-dropforeigntable.html" title="DROP FOREIGN TABLE">Prev</a> </td><td width="20%" align="center"><a accesskey="u" href="sql-commands.html" title="SQL Commands">Up</a></td><td width="40%" align="right"> <a accesskey="n" href="sql-dropgroup.html" title="DROP GROUP">Next</a></td></tr><tr><td width="40%" align="left" valign="top">DROP FOREIGN TABLE </td><td width="20%" align="center"><a accesskey="h" href="index.html" title="PostgreSQL 16.3 Documentation">Home</a></td><td width="40%" align="right" valign="top"> DROP GROUP</td></tr></table></div></body></html>